Consistency of protocol and safety data reporting in clinical trial registrations and corresponding publications of interventions involving MDMA and psilocybin.
Journal of clinical epidemiology January 23, 2026 Marija Franka Žuljević, Antonija Mijatović, Renata Orhanović et al. 4 citations
A cross-sectional analysis of 336 clinical trials on MDMA or psilocybin registered on ClinicalTrials.gov found that 17.6% made major changes to primary outcome measures and 28.6% changed eligibility criteria, most after recruitment began. Among completed trials, 72.0% did not post results on the registry, and most that did exceeded the one-year reporting window. Only 3 of 29 trials with both posted results and publications had fully concordant adverse event reporting; most showed qualitative and quantitative discrepancies. These inconsistencies undermine the credibility and safety evaluation of these trials, and the authors advise greater transparency and stricter adherence to reporting standards.